Photoelectronic device

ABSTRACT

A photoelectronic device including a carrier, a light-emitting component mounted on the carrier; a patterned structure deposited on the carrier and around the light-emitting component; and a transparent sealing structure formed above the light-emitting component. The patterned structure mentioned above can cause the transparent sealing structure to be focused above the light-emitting component, and restrained in the patterned structure. The transparent sealing structure with predetermined proportional configuration is obtained by controlling the quantity of the transparent sealing structure. Therefore light efficiency of the photoelectronic device can be greatly improved.

TECHNICAL FIELD

The present invention relates to a photoelectronic device, especially toa light-emitting device having a transparent sealing structure withpredetermined dimensional configuration.

REFERENCE TO RELATED APPLICATION

This application claims the right of priority based on TW applicationSer. No. 096140915, filed “Oct. 29, 2007”, entitled “PhotoelectronicDevice” and the contents of which are incorporated herein by reference.

BACKGROUND

Light-emitting diode (LED) is of much importance in solid-state deviceswith a characteristic of photo-electronic conversion. Generallyspeaking, LED has an active layer sandwiched by two semiconductor layerswith different conductivity types. When driving current is applied toelectrodes above the two semiconductor layers, electrons and holes ofthe two semiconductor layers inject into and combine with each other inthe active layer to emit light. The light is omni-directional, so itemits out from the active layer to each surface of the LED.

Meanwhile, LED is also widely used as a light source. Comparing withtraditional incandescent lamp or fluorescent lamp, LED has outstandingfeatures like efficient energy and long lifetime. Therefore, LEDgradually takes the place of the traditional light sources and be widelyused in a variety of fields such as traffic signals, backlight module,street lamp lighting and medical treatment devices. As the LED lightsources develop and have more applications, the demand of luminance isgrowing higher. Hence, how to increase the light efficiency of LEDs toimprove luminous thereof is an important direction for the industry tostrive for.

The field worthy of studying is how to increase light efficiency by adesign of sealing structure. At present a cup-like structure isgenerally adopted, and LED is disposed at a center of the cup to controlthe light distribution by taking advantage of the shapes of the cup andsealing materials. In addition, sealing materials, the reflectionability of the carrier, the shape of the cup and so on can also affectlight efficiency.

In view of the foregoing, there is a need of a photoelectronic devicethat provides the improvement of light efficiency.

SUMMARY

In one embodiment, the present invention provides a photoelectronicdevice which comprises: a carrier; a light-emitting component depositedon the carrier; a patterned structure deposited on the carrier andaround the light-emitting component; and a transparent sealing structureformed above the light-emitting component. The patterned structurementioned above can restrict the transparent sealing structure to befocused in the region between the patterned structure and light-emittingcomponent. Transparent sealing structure with predetermined dimensionalconfiguration is produced by controlling the quantity of sealing in thetransparent sealing structure. Wherein the light-emitting component canbe an LED device, or any device with photo-electronic conversioncharacteristic.

The present invention provides a photoelectronic device which comprises:a carrier, a light-emitting component deposited on the carrier with amaximum width of z; and a transparent sealing structure formed above thelight-emitting component with a height of y and a projected maximumlength of x onto a surface of the carrier. Wherein the ratio of y to xis from 0.4 to 0.8, and wherein the ratio of z to x is from 0.3 to 0.5.

The present invention provides a photoelectronic device which comprises:a carrier having a protrusion portion with a bottom width of b; alight-emitting component connected to top of the protrusion portion witha maximum width of a; and a transparent sealing structure covering theprotrusion portion and light-emitting component with a length of c.Wherein the light-emitting component is deposed proximately to aposition of c/2, and a ratio of a to b is less than or equal to 3. Thetransparent sealing structures with various predetermined dimensionalconfiguration of the present invention can improve the light efficiencyof the light-emitting component.

Broadly speaking, the present invention fulfills the need by providingan improved photoelectronic device to increase light efficiency. Itshould be appreciated that the present invention can be implemented innumerous ways, including as a process, an apparatus or a system. Severalinventive embodiments of the present invention are described below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic view of the photoelectronic device of a firstembodiment.

FIG. 2 shows a schematic view of the photoelectronic device of a secondembodiment.

FIG. 3 shows a schematic view of the photoelectronic device of a thirdembodiment.

FIG. 4A shows a graph of a relation between light efficiency and ratioof y to x.

FIG. 4B shows a graph of a relation between light efficiency and ratioof z to x.

FIG. 5 shows a schematic view of the photoelectronic device of a fourthembodiment.

FIG. 6 shows a schematic view of the photoelectronic device of a fifthembodiment.

FIG. 7 shows a schematic view of a backlight module of the presentinvention.

FIG. 8 shows a schematic view of a lighting device of the presentinvention.

DETAILED DESCRIPTION

Several exemplary embodiments for an improved photoelectronic device isnow described. It is apparent to those skilled in the art that thepresent invention may be practiced without some or all of the specificdetails set forth herein. It is also apparent to those skilled in theart that the present invention may be practiced for backlight module orlighting device.

FIG. 1 shows a schematic view of the photoelectronic device of a firstembodiment, wherein structural elements that each reference numeraldesignates is described as follow: 104 for a carrier, 102 for areflective layer, 103 for a light-emitting component, 105 for atransparent sealing structure, and 107 for a patterned structure. Itshould be appreciated that like structural elements in other figureshereinafter are designated by like reference numerals, and will notdescribe below.

Referring to FIG. 1, the photoelectronic device of the embodiment isessentially formed as below: firstly, forming a reflective layer 102with high reflectivity onto a surface of a flat carrier 104; and thenforming a light-emitting component 103 onto the reflective layer 102;after that, spreading a layer of patterned structure 107 withhydrophobic property around the light-emitting component 103 to form apattern like circular, rectangle or square. Afterwards, a transparentsealing material is formed above the light-emitting component 103 by anadhesive dispensing technique. The patterned structure 107 withhydrophobic property can make the transparent sealing materialrestrained to a range between the patterned structure 107 and thelight-emitting component 103. Simultaneously, during adhesivedispensing, as shown in FIG. 1, transparent sealing structure 105 withprotrusion is produced by controlling the quantity of the transparentsealing material. The photoelectronic device produced by the stepsaforementioned can make the light of the light-emitting component 103emitting from the transparent sealing structure 105 after beingreflected by the reflective layer 102. Light efficiency can be greatlyimproved by the design of the reflective layer 102 and the transparentsealing structure 105.

Wherein, the maximum width of the light-emitting component 103 is z, theheight of the transparent sealing structure 105 is y, and the maximumlength of a contact area between the transparent sealing structure 105and the reflective layer 102 is x. When a ratio of y to x is from 0.4 to0.8, light efficiency is much higher, and preferably to be 0.6. In themeantime, when a ratio of z to x is from 0.3 to 0.5, better lightefficiency could also be obtained, and preferably to be 0.4.

The carrier 104 could be a printed circuit board (PCB), flexible printedcircuit board (FPCB), ceramic substrate or composite substrate. Besidessupporting the light-emitting component 103, the carrier 104 furtherdissipates heat produced by the light-emitting component 103 andtherefore achieving heat dissipation. The reflective layer 102 has highreflection coefficient, and can be made of Au, Ag, Al, Cu or alloys of acombination of the above, and can also be made of a polymer materialwith reflective property. The color of light emitted from thelight-emitting component 103 could be red, blue, green, yellow, etc. Thepatterned structure 107 is made of materials with hydrophobic property.Surface tension may exist between such materials and the transparentsealing material which makes the transparent sealing material focus in aregion between the patterned structure 107 and the light-emittingcomponent 103, therefore generating a protuberant transparent sealingstructure 105. Wherein the patterned structure 107 could be a polymermaterial with hydrophobic functional group, such as methyl group orfluorine group. The fabrication of the patterned structure 107 is asbelow: producing the polymer material by sol-gel method orpolymerization method, and then forming predetermined patterns such ascircular, rectangle or square on a surface of the carrier 104 by screenprinting process, inject printing process, etc. The transparent sealingstructure 105 is produced by forming a transparent sealing materialabove the light-emitting component 103 by adhesive dispensing technique,and then heating for curing. The transparent sealing material can be anorganic insulating material with high light transmitting property, suchas epoxy, poly-imides, silicon resin or a mixture of the above mentionedmaterials.

FIG. 2 shows a photoelectronic device of a second embodiment. Asdescribed in the first embodiment, after forming a reflective layer 102with high reflectivity, light-emitting component 103 is formed above thereflective layer 102. Afterwards, transparent sealing material isdispensed above the light-emitting component 103 by adhesive dispensingtechnique. The transparent sealing structure 105 with particularprotrusion shape is produced by controlling the quantity of thetransparent sealing material. To obtain optimal light efficiency, theshape of the transparent sealing structure 105 must be deliberatelydesigned. Referring to FIG. 2, the maximum width of the light-emittingcomponent 103 is z, the height of the transparent sealing structure 105is y, the maximum length of the contact surface between the transparentsealing structure 105 and the reflective layer 102 is x. Thelight-emitting component 103 could be a commonly known chip with a sizeof 15 to 40 mils. By tuning the adhesive dispensing condition; a varietyof protrusion shape of the transparent sealing structure 105 is formedabove the light-emitting component 103, so as to obtain lightefficiencies at different ratio of y to x. Taking the two, i.e., thelight efficiencies and the ratio of y to x, as the coordinates to plot arelationship graph as shown in FIG. 4A. Referring to FIG. 4A, when theratio of y to x is from 0.4 to 0.8, the light efficiency is much higher;preferably when the ratio of y to x is near 0.6, the light efficiency isthe highest. Moreover, when the ratio of y to x of the transparentsealing structure 105 is fixed in 0.5, the light efficiency is measuredwith different ratios of z to x, and then take the two, i.e., the lightefficiency and the ratio of z to x, as the coordinates to plot arelationship graph as shown in FIG. 4B. When the ratio of z to x is from0.3 to 0.5, the light efficiency is much higher; preferably when theratio of z to x is near 0.4, the light efficiency is highest.

FIG. 3 shows a photoelectronic device of a third embodiment, furthercomprises a fluorescent powder layer 108 spreading onto the surface ofthe light-emitting component 103 to convert wavelength. Thelight-emitting component 103 can be an InGaN series light emitting diodewhich is capable of emitting blue light, and generating white light byexciting an YGA series yellow fluorescent powder layer 108.

A fourth embodiment of the present invention is shown in FIG. 5.Comparing with the second embodiment, a plurality of light-emittingelements 123, 133 and 143 take place of the light-emitting component 103in the second embodiment, wherein the light-emitting elements 123, 133and 143 emit different colored lights such as red, green and bluerespectively. The lights aforementioned are mixed in the transparentsealing structure 105 to produce white light. As is shown, the maximumwidth of the series made up by the plurality of light-emitting elements123, 133 and 143 is z, the height of the transparent sealing structure105 is y, the maximum length of the contact surface between thetransparent sealing structure 105 and the reflective layer 102 is x. Aratio of y to x is from 0.4 to 0.8, preferably 0.6, and a ratio of z tox is from 0.3 to 0.5, preferably 0.4.

A fifth embodiment of the present invention is shown in FIG. 6, which isa bulb-like photoelectronic device, comprising a carrier 202 withprotrusion portion 203; a light-emitting component 204 formed above theprotrusion portion 203; and a transparent sealing structure 205 coveringthe protrusion portion 203 and the light-emitting component 204. Whereinthe width of the light-emitting component 204 is a, the bottom width ofthe protrusion portion 203 is b, and the height of the transparentsealing structure 205 is c. To improve light efficiency of the bulb-likephotoelectronic device, a ratio between the width of the light-emittingcomponent 204 and the bottom width of the protrusion portion 203 is a tob, preferably less than or equal to 3. The light-emitting component 204is located proximately to the position of c/2. Moreover, thelight-emitting component 204 can be placed by a plurality oflight-emitting elements with different colors, such as by white lightsource consisted by red, green, and blue light. Simultaneously, apatterned structure 206 is also formed near the bottom of the protrusionportion 203, which restricts the transparent sealing structure 205 abovethe protrusion portion 203, therefore obtain a near circular sphere.

FIG. 7 shows a backlight module, wherein the backlight module 700comprises a light source device 710 constituted by photoelectronicdevice 711 described in any embodiment above; an optical device 720placed at emission path of the light source device 710 for processingthe light emitted from the light source device 710; and a power supplysystem 730 to provide power needed by the light source device 710.

FIG. 8 shows a lighting device 800, which could be car lamp, streetlamp,flashlight, road lamp and indicator lamp etc. Wherein the lightingdevice 800 comprises a light source device 810 constituted byphotoelectronic device 811 as described in above embodiments; a powersupply system 820 to provide power needed by the light source device810; and a control element 830 used to control input current to thelight source device 810.

The above description is given by way of example, and not limitation.Given the above disclosure, one skilled in the art could devisevariations that are within the scope and spirit of the inventiondisclosed herein, including configurations ways of the recessed portionsand materials and/or designs of the attaching structures. Further, thevarious features of the embodiments disclosed herein can be used alone,or in varying combinations with each other and are not intended to belimited to the specific combination described herein. Thus, the scope ofthe claims is not to be limited by the illustrated embodiments.

1. A photoelectronic device, comprising: a carrier; a light-emittingcomponent deposed on the carrier; a patterned structure deposed on thecarrier and around the light-emitting component; and a transparentsealing structure, formed above the light-emitting component, andlocated between the patterned structure and the light-emittingcomponent.
 2. The photoelectronic device as described in claim 1,wherein the surface of the carrier is flat.
 3. The photoelectronicdevice as described in claim 1, wherein the transparent sealingstructure is protuberant from the carrier.
 4. The photoelectronic deviceas described in claim 1, wherein the patterned structure is made frommaterials with hydrophobic property.
 5. The photoelectronic device asdescribed in claim 4, wherein the materials with hydrophobic property isa polymer material with functional group of methyl or fluorine.
 6. Thephotoelectronic device as described in claim 1, further comprising afluorescent powder layer covered on the light-emitting component.
 7. Thephotoelectronic device as described in claim 1, wherein thelight-emitting component has a maximum width of z; the transparentsealing structure has a height of y and a projected maximum length of xonto a surface of the carrier, wherein a ratio of y to x is from 0.4 to0.8, preferably 0.6; and a ratio of z to x is from 0.3 to 0.5,preferably 0.4.
 8. The photoelectronic device as described in claim 1,further comprising a reflective layer positioned between the carrier andthe light-emitting component.
 9. A photoelectronic device, comprising: acarrier; a light-emitting component deposed on the carrier and having amaximum width of z; and a transparent sealing structure formed above thelight-emitting component and having a height of y and a projectedmaximum length of x onto a surface of the carrier; wherein a ratio of yto x is from 0.4 to 0.8.
 10. The photoelectronic device as described inclaim 9, wherein a ratio of y to x is about 0.6.
 11. The photoelectronicdevice as described in claim 9, wherein a ratio of z to x is from 0.3 to0.5.
 12. The photoelectronic device as described in claim 9, wherein aratio of z to x is about 0.4.
 13. The photoelectronic device asdescribed in claim 9, further comprising a fluorescent powder layercovered on the light-emitting component.
 14. The photoelectronic deviceas described in claim 9, further comprising a reflective layer locatedunder the light-emitting component.
 15. The photoelectronic device asdescribed in claim 9, wherein the light-emitting component including aplurality of light-emitting elements, wherein the maximum width of zrefers to a maximum width of a series made up by the plurality oflight-emitting elements.
 16. The photoelectronic device as described inclaim 9, further comprising a patterned structure deposited on thecarrier and around the light-emitting component.
 17. A photoelectronicdevice, comprising: a carrier, having a protrusion portion with a bottomwidth of b; a light-emitting component with a maximum width of a,connected to the top of the protrusion portion, and a transparentsealing structure with a length of c, covering the protrusion portionand the light-emitting component.
 18. The photoelectronic device asdescribed in claim 17, wherein a ratio of a to b is less than or equalto
 3. 19. The photoelectronic device as described in claim 17, whereinthe light-emitting component can be placed by a plurality oflight-emitting elements with different color.
 20. The photoelectronicdevice as described in claim 17, further comprising a patternedstructure formed adjacent to the bottom of the protrusion portion.